Conveyor belts are used to transport materials or goods from one place to another. Conveyor belts are often provided in predetermined lengths that require belt fasteners to secure the two ends of the belt length together to form a continuous belt. Conveyor belt fasteners are also used to repair conveyor belts that become damaged such as by ripping or tearing during operation. The belt fasteners can be of the hinged-type and can be stapled, riveted, or otherwise secured to the belt ends and are thereafter joined together by a hinge pin.
U.S. Pat. No. 4,060,877 to Schick discloses one type of fastener having spaced arms for being secured to an end of a conveyor belt and a hinge knuckle connecting the arms. The fastener arms are secured to one end of a conveyor belt and the hinge knuckle interengages with hinge knuckles projecting from fastener arms secured to the other end of the conveyor belt. The hinge knuckles are coupled together by a hinge pin that is passed through openings formed by the interengaged hinge knuckles. The hinge knuckle of each fastener has a reduced width relative to the fastener arms to permit the interengagement between the hinge knuckles. The reduced width may reduce the strength of the fastener at the hinge knuckle where the fastener is subject to high loading forces as the conveyor belt and fastener thereon travel over pulleys or rollers of the conveyor belt system.
The '877 patent discloses that the fastener is fabricated from a piece of sheet metal having a width practically constant over its entire length. To form the hinge knuckle, the sides of the piece sheet metal are folded back against each other to reside in a plane substantially perpendicular to clamping tongues of the fastener. The '877 patent discloses that this process of folding back the sheet metal to form a U-shaped cross-section of the hinge knuckle strengthens the hinge knuckle. However, the step of folding back the sheet metal to form the u-shaped cross-section of the hinge-knuckle complicates manufacture of the fastener and increases the production cost of the fasteners due to the need to change the flat cross-section of the piece of sheet metal to the U-shaped configuration of the fastener hinge knuckle.
U.S. Pat. No. 5,182,933 to Schick discloses a method of producing U-shaped clips for interconnecting conveyor belts. The clips are formed using deep drawing and pressing operations performed consecutively on a metal strip. The clips have upper and lower arms each with apertures through which rivets or fixing staples will extend to fix the clip to one of the ends of the conveyor belt. Loading from conveyor belt operations could cause cracks or areas of weakness to form in the upper and lower arms that spread from the apertures outwardly along the arms. Because the sections of the upper and lower arms that contain the apertures are flat, the ability of the arms to resist crack propagation is dependent on the thickness of the arm sections. Increasing the thickness of the arm sections may make the arm sections stronger and better able to resist crack propagation from the apertures, but the increased thickness of the arm sections increases the height or profile of the clips on the conveyor belt. The increased height of the clips on the conveyor belt produces greater wear and tear on conveyor belt cleaners since the taller clips strike the conveyor belt cleaners with every rotation of the conveyor belt.